Add decoding empty buffer test calls for cipher modes that benefit from this
diff --git a/tests/suites/test_suite_cipher.blowfish.data b/tests/suites/test_suite_cipher.blowfish.data
index b94bc47..627c42b 100644
--- a/tests/suites/test_suite_cipher.blowfish.data
+++ b/tests/suites/test_suite_cipher.blowfish.data
@@ -1,3 +1,7 @@
+BLOWFISH CBC Decrypt empty buffer
+depends_on:MBEDTLS_BLOWFISH_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_CIPHER_PADDING_PKCS7
+dec_empty_buf:MBEDTLS_CIPHER_BLOWFISH_CBC
+
BLOWFISH Encrypt and decrypt 0 bytes
depends_on:MBEDTLS_BLOWFISH_C:MBEDTLS_CIPHER_MODE_CBC:MBEDTLS_CIPHER_PADDING_PKCS7
enc_dec_buf:MBEDTLS_CIPHER_BLOWFISH_CBC:"BLOWFISH-CBC":128:0:-1